Processes and systems for alcohol production and recovery

Abstract

The present invention relates to processes for recovering butanol produced in a fermentative process using, for example, an ethanol production plant which has been reversibly-retrofitted for butanol production, that is, the ethanol production plant may be converted for butanol production, but can also revert to an ethanol production. The present invention also relates to processes for recovering butanol produced in a fermentative process in a butanol production plant that may be converted to ethanol production plant.

What is claimed is: 
     
       1. A method for improving the product profile of an ethanol production plant comprising modifying the plant to produce one or more biofuel products other than ethanol wherein modifying the plant comprises
 adding a mixing device and a separation system to an external cooling loop of a fermentor, adding one or more separation units, 
 separating a feedstock slurry prior to fermentation to form streams: (i) an aqueous solution comprising fermentable sugars, (ii) a wet cake comprising undissolved solids, and (iii) an oil stream, 
 adding one or more extractant columns and/or extractant separation units, 
 repurposing an ethanol beer column for distillation of an alcohol other than ethanol, and reconfiguring an evaporation train, 
 
       wherein the modifications allow the plant to be reverted to ethanol production. 
     
     
       2. The method of  claim 1 , further comprising adding one or more condensation units and/or adding one or more decantation units. 
     
     
       3. A method for improving the product profile of an ethanol production plant comprising modifying the plant to produce one or more biofuel products other than ethanol wherein modifying the plant comprises
 adding a mixing device and a separation system to an external cooling loop of a fermentor, 
 adding one or more separation units, 
 separating a feedstock slurry prior to fermentation to form streams: (i) an aqueous solution comprising fermentable sugars, (ii) a wet cake comprising undissolved solids, and (iii) an oil stream, 
 adding one or more flash units and/or condensation units, 
 repurposing an ethanol beer column for distillation of an alcohol other than ethanol, and 
 reconfiguring an evaporation train, 
 
       wherein the modifications allow the plant to be reverted to ethanol production. 
     
     
       4. The method of  claim 3 , further comprising adding one or more preflash units and/or compressor units. 
     
     
       5. The method of  claim 1 , further comprising adding one or more hydrolyzers. 
     
     
       6. The method of  claim 1 , wherein the one or more biofuel products comprises butanol. 
     
     
       7. The method of  claim 1 , wherein the one or more biofuel products comprises butanol and fusel oils. 
     
     
       8. The method of  claim 1 , wherein the one or more biofuel product comprises butanol and oil. 
     
     
       9. The method of  claim 1 , wherein the one or more separation units is selected from decanter bowl centrifugation, three-phase centrifugation, disk stack centrifugation, filtering centrifugation, decanter centrifugation, filtration, vacuum filtration, beltfilter, pressure filtration, filtration using a screen, screen separation, grating, porous grating, flotation, hydrocyclone, filter press, screwpress, gravity settler, vortex separator, and combinations thereof. 
     
     
       10. The method of  claim 1 , wherein the one or more extraction separation units is selected from hydrocyclone, centrifuge, inline vortex separator, decanter, filter, siphon, mixer-settler, gravity settler, and combinations thereof. 
     
     
       11. The method of  claim 1 , wherein the one or more extraction columns comprises a rectification section. 
     
     
       12. The method of  claim 1 , wherein the evaporation train is configured as a four train, double effect evaporation system, a three train, triple effect evaporation system, or a two train, quadruple effect evaporation system. 
     
     
       13. The method of  claim 1 , further comprising adding a methanator. 
     
     
       14. The method of  claim 1 , further comprising adding solids washing equipment comprising one or more centrifuges and a conveyor, wherein the wet cake is further processed by the solids washing equipment. 
     
     
       15. The method of  claim 3 , wherein the one or more separation units is selected from decanter bowl centrifugation, three-phase centrifugation, disk stack centrifugation, filtering centrifugation, decanter centrifugation, filtration, vacuum filtration, beltfilter, pressure filtration, filtration using a screen, screen separation, grating, porous grating, flotation, hydrocyclone, filter press, screwpress, gravity settler, vortex separator, and combinations thereof. 
     
     
       16. The method of  claim 3 , further comprising adding one or more condensation units. 
     
     
       17. The method of  claim 3 , wherein the evaporation train is configured as a four train, double effect evaporation system, a three train, triple effect evaporation system, or a two train, quadruple effect evaporation system. 
     
     
       18. The method of  claim 3 , further comprising adding a methanator. 
     
     
       19. The method of  claim 3 , further comprising adding solids washing equipment comprising one or more centrifuges and a conveyor, wherein the wet cake is further processed by the solids washing equipment. 
     
     
       20. The method of  claim 3 , wherein the one or more biofuel products comprises butanol. 
     
     
       21. The method of  claim 1 , wherein the mixing device is an inline mixer or piping tee. 
     
     
       22. The method of  claim 1 , wherein the separation system is hydrocyclone, centrifuge, inline vortex separator, decanter, or filter. 
     
     
       23. The method of  claim 3 , wherein the mixing device is an inline mixer or piping tee. 
     
     
       24. The method of  claim 3 , wherein the separation system is hydrocyclone, centrifuge, inline vortex separator, decanter, or filter.